Abstract

The Functional Assessment of Chronic Illness Therapy (FACIT) Measurement System is
a collection of health-related quality of life (HRQOL) questionnaires targeted to
the management of chronic illness. The measurement system, under development since
1987, began with the creation of a generic CORE questionnaire called the

F

unctional

A

ssessment of

C

ancer

T

herapy-

G

eneral (FACT-G). The FACT-G (now in Version 4) is a 27-item compilation of general
questions divided into four primary QOL domains: Physical Well-Being, Social/Family
Well-Being, Emotional Well-Being, and Functional Well-Being. It is appropriate for
use with patients with any form of cancer, and extensions of it have been used and
validated in other chronic illness condition (e.g., HIV/AIDS; multiple sclerosis;
Parkinson's disease; rheumatoid arthritis), and in the general population. The FACIT
Measurement System now includes over 400 questions, some of which have been translated
into more than 45 languages. Assessment of any one patient is tailored so that the
most-relevant questions are asked and administration time for any one assessment is
usually less than 15 minutes. This is accomplished both by the use of specific subscales
for relevant domains of HRQOL, or computerized adaptive testing (CAT) of selected
symptoms and functional areas. FACIT questionnaires can be administered by self-report
(paper or computer) or interview (face-to-face or telephone). Available scoring, normative
data and information on meaningful change now allow one to interpret results in the
context of a growing literature base.

Review

What is the FACIT Measurement System?

The FACIT Measurement System is a collection of health-related quality of life (HRQOL)
questionnaires targeted to the management of chronic illness. "FACIT" (Functional
Assessment of Chronic Illness Therapy) was adopted as the formal name of the measurement
system in 1997 to portray the expansion of the familiar "FACT" (Functional Assessment
of Cancer Therapy) questionnaires into other chronic illnesses and conditions.

The measurement system, under development since 1987, began with the creation of a
generic CORE questionnaire called the

F

unctional

A

ssessment of

C

ancer

T

herapy-

G

eneral (FACT-G). The FACT-G (now in Version 4) is a 27-item compilation of general
questions divided into four primary QOL domains: Physical Well-Being, Social/Family
Well-Being, Emotional Well-Being, and Functional Well-Being. It is considered appropriate
for use with patients with any form of cancer, and has also been used and validated
in other chronic illness condition (e.g., HIV/AIDS and multiple sclerosis) and in
the general population (using a slightly modified version).

Validation of a core measure allowed for the evolution of multiple disease, treatment,
condition, and other targeted questionnaires. FACIT scales are constructed to complement
the FACT-G, addressing relevant disease-, treatment-, or condition-related issues
not already covered in the general questionnaire. Each is intended to be as specific
as necessary to capture the clinically-relevant problems associated with a given condition
or symptom, yet general enough to allow for comparison across diseases, and extension,
as appropriate, to other chronic medical conditions. The latest version of the FACIT
Measurement System, Version 4, was designed to enhance clarity and precision of measurement
without threatening its established reliability and validity (from Version 3). Formatting
simplification, item-reduction, and rewording (standardizing items across scales)
constitute the major areas of change from version 3 to 4. To facilitate the clinical
utility of the FACIT system, new methods for computer acquisition, scoring, and display
of data will be available. These additions and improvements will likely ease patient
burden, expedite data collection and scoring, and further guide the clinician or researcher
in meaningful interpretation.

Why assess health-related quality of life with the FACIT Measurement System?

The FACIT Measurement System offers several benefits to an investigator seeking to
measure HRQOL in people with cancer, HIV disease, multiple sclerosis, arthritis and
other conditions. First, item content was determined by combined expert and patient
input, ensuring that clinically important issues relevant to patients are included.
Second, there are several hundred publications detailing its performance, many of
which are reports of formal validation studies. Thus, there is a deep reference literature
to which one can compare results. A third advantage to FACIT is the availability of
normative and cross-illness comparative scores to which one can relate results. Finally,
a growing body of research has illustrated clinically significant differences and
changes in scores in FACIT scales, aiding in study sample size determination and interpretation
of study results.

How was the FACIT developed and validated?

Most FACIT measures have undergone a standard scale development and validation methodology,
which takes place in four phases: item generation, item-reduction, scale construction,
and psychometric evaluation [1-22]. The scale development process involves considerable input from patients and expert
health care providers, using a semi-structured interview designed to elicit personal
experiences and educated opinions about how a disease, treatment, or condition may
affect physical status, emotional well-being, functional well-being, family /social
issues, sexuality/intimacy, work status, and future orientation. This process yields
an exhaustive list of candidate items, which then undergo a series of reviews and
reductions based on patient and expert ratings and item quality. A finite set of targeted
concerns are then derived. Final candidate items are formatted with response choices
compatible with a 5-point Likert-type scale, and appended to the FACT-G.

Newly constructed FACIT subscales then undergo an initial assessment of reliability
and validity using a sample of at least 50 patients. The validation design typically
involves patient completion of a baseline assessment, a test-retest assessment 3–7
days later, and a third assessment 2–3 months later to demonstrate sensitivity to
change over time. Relevant sociodemographic and treatment data is also collected and
a battery of other measures administered at the baseline and 2–3 month retest to help
determine convergent and divergent validity. A comprehensive analysis of the data
gathered (including item response theory modeling when sample size allows) yields
useful psychometric information and establishes initial reliability and validity of
the scale.

The FACIT Translation Project team has developed a scientific approach to translating
patient reported outcomes measures, which includes a rigorous forward-backward-forward
methodology, psychometric testing, and cognitive interviewing. This process was developed
to ensure that the resulting measures are both conceptually equivalent as well as
cross-culturally valid, thus enabling data pooling in multinational clinical trials
that enroll patients who speak various languages.

The FACIT Translation Project was initiated to fulfill a need for valid and reliable
HRQOL assessment instruments in languages other than English as part of the FACIT
Measurement System. The translation methodology developed for the FACIT project has
proven to be successful in adapting questionnaires into European, Asian and African
languages. The list of available languages has grown, keeping pace with the globalization
of medical outcomes research.

Why are the FACIT questionnaires good instruments to consider using?

There are many questionnaires available to measure HRQOL of people with chronic illnesses.
The FACIT questionnaires are some of the more commonly used questionnaires in national
and international research settings. Selecting an appropriate outcome measure is often
driven by many considerations including the purpose of the study, the patient-reported
endpoint required to address the study purpose, the content of the items in the questionnaire
with regard to the study purpose, and the validity of the questionnaire. Although
no single questionnaire is right for all studies, the FACIT Measurement System provides
an array of generic and targeted measures with multiple benefits regarding validity,
ease of administration, global application, and interpretation.

• Approximately 50 different generic and targeted questionnaires and symptom indices

What are the applications of the FACIT?

Current implementation of the FACIT questionnaires range in use from Phase I, II,
and III clinical trials and other treatment evaluations, as an intervention tool in
the clinical management of symptoms (both physical and psychological), and as an outcomes
measure in health practice studies.

How long does it take to complete?

Respondent burden is typically minimal given that the questionnaire is written at
the 4th grade-reading level, and is specifically formatted for ease of self-administration.
Average time to complete the 27-item FACT-G is 5–10 minutes, and even less for the
stand-alone scales and symptom indices. As a rule of thumb, it takes 2–3 minutes to
complete 10 questions, so administration length can be estimated after one selects
the subscales to be combined in one's assessment plan. The option to complete the
questionnaire by interview decreases burden for patients whose condition (e.g. fatigue;
poor eyesight) or mood preclude them from completing the questionnaire by self-administration,
but may increase completion time.

How is the FACIT administered?

The FACIT scales are designed for patient self-administration, either on paper or
direct to computer. They can also be administered using face-to-face or telephone
interview. Interview administration is appropriate with adequate training of interviewers
to minimize bias to patient responses. One of the aims of a large multicenter study
of cancer and HIV patients (N = 1615) was to test the psychometric properties and
statistical equivalence of the English and Spanish language versions of the FACT subscales
across literacy level (low vs. high) and mode of administration (self report vs. interview).
Technical equivalence across mode of administration was demonstrated in the high literacy
patients; there were few differences in data quality or psychometric measurement properties
of the FACT-G. Technical equivalence between modes of administration with the FACT
permits unbiased assessment of the impact of chronic illnesses and their treatments
on patients from diverse backgrounds [23].

We have additional data to support the appropriateness of computer-administered versions
of the questionnaire, including a multimedia touchscreen program [24]. We are currently developing other novel administration methods such as computer-assisted
telephony and web-based administration. Across these modes of administration, our
preliminary data suggest that while there are small differences in the way people
respond based on mode of administration, these alternate formats are essentially equivalent.

How is the FACIT scored?

All FACIT scales are scored so that a high score is good. To achieve this, we reverse
response scores on negatively-phrased questions, then sum item responses. In cases
where individual questions are skipped, scores are prorated using the average of the
other answers in the scale. The total FACT-G score is obtained by summing individual
subscale scores (PWB + EWB + SWB + FWB). Total scores for the disease-, treatment-,
and condition-specific subscales are obtained by summing all subscale scores (PWB
+ EWB + SWB + FWB + additional concerns subscale). For these scales there is also
the option to calculate a Trial Outcome Index (TOI). The TOI can be computed for any
FACIT disease-, treatment-, or condition-specific scale. It is the sum of the Physical
Well-Being (PWB), Functional Well-Being (FWB), and "additional concerns" subscales.
Our experience with this TOI endpoint is that it is an efficient summary index of
physical/functional outcomes. It is therefore a common endpoint used in clinical trials,
because it is responsive to change in physical/functional outcomes, sometimes more
than a total (overall) multidimensional aggregated score, which includes social and
emotional well-being. While social and emotional well-being are very important to
quality of life, they are not as likely to change as quickly or dramatically over
time or in response to physical health interventions such as pharmaceutical treatments
in clinical trials.

When there are missing data, prorating subscale scores is acceptable as long as more than 50% of the items were answered (e.g., a minimum of 4 of 7 items, 4 of 6 items, etc).
The total (FACT-G) score is considered appropriate to score as long as overall item response rate is greater than 80% (e.g., at least 22 of 27 FACT-G items completed).

Is there automated administration or scoring software?

Raw score scoring templates and computer scoring programs written for use with both
SAS and SPSS statistical software packages are available for all FACIT measures. We
are currently developing computer-administered programs for various FACIT questionnaires.
Packages will include a patient-friendly computer-administered questionnaire, with
automatic scoring and the ability to plot individual patient scores longitudinally
on a reader-friendly graph. Some programs may also offer plotted graphs with patient
and normative reference data. We expect to have these programs available by the end
of 2003. See http://www.facit.orgwebcite for updates.

How are FACIT scores interpreted?

Higher scores for the scales and subscales indicate better quality of life. Average
FACT-G scores for a group of patients can be compared to normative data to determine
the HRQOL of the patients relative to the general U.S. population. These comparisons
facilitate meaningful interpretation of HRQOL in patient populations.

Normative data for the FACT-G and the 13-item fatigue subscale have been collected
on 1,075 men and women drawn from the general U.S. population. The range of ages in
the sample was 18 to 91 years with a mean (s.d.) of 45.9 (16.6), 50.6% were female,
75.9% were white, and 87.8% had at least a high school education. Means (s.d.) for
FACT-G and fatigue subscale scores were 80.1 (18.1) for total FACT-G; 22.7 (5.4) for
PWB; 19.1 (6.8) for SWB; 19.9 (4.8) for EWB; 18.5 (6.8) for FWB, and 40.1 (10.4) for
the fatigue subscale. Normative data have also been established separately for males
and females and for 10-year age groups. For more information on U.S. population norms
for the FACT-G visit our website at http://www.facit.orgwebcite.

Are the FACIT questionnaires responsive to change? What is a meaningful change in
a FACIT score?

The FACIT instruments have been shown to be responsive to change in both clinical
and observational studies. Considerable work has been done in recent years to identify
minimally important differences (MIDs) for scores of scales and subscales from several
FACIT instruments. An MID is the "smallest difference in score in the domain of interest
that patients perceive as important, either beneficial or harmful, and that would
lead the clinician to consider a change in the patient's management" (p 377) [25]. MIDs were identified using both anchor- and distribution-based methods [26]. MID estimates may vary across patients and possibly across patient groups; thus,
ranges of MIDs were identified for some scales. As TOIs are frequently used measures
of QoL, MIDs have been established for the TOIs for several FACIT instruments. Table
1 provides a list of established MIDs:

These MIDs can be used to aid the interpretation of group differences and changes
in HRQOL over time, and they can be useful in sample size calculations.

Has the FACIT been used in individual patient assessment?

Yes. The FACT-G has been used extensively in clinic-based evaluations of individual
patients. Instruments like the FACT-G, relatively brief, multidimensional questionnaires,
are designed primarily for group comparisons, lacking precision needed for individual
diagnosis. Nevertheless, individual assessment using the FACT-G has been helpful to
patients and clinicians attempting to estimate change over time. It can also be a
useful "springboard" for discussion. We have developed more accurate assessment from
our item response theory (IRT)-derived item-banks that are indeed sufficiently precise
for individual diagnosis. Each of our IRT-derived item banks (pain, fatigue, physical
function, emotional distress, etc.) can be administered to patients using a computerized
assessment algorithm, which selects only those questions that will add to the precision
of the measurement estimate. This procedure, called computerized adaptive testing
(CAT), results in brief, accurate assessment of the selected HRQOL domains.

Is there Item Banking of the FACIT Questionnaires?

Yes. Our item-banking program is very active. There are two types of item banks. The
first is a simple compilation of all items (questions) available in our database.
We have over 400 questions in this "general" item bank, and most of them have been
translated into several languages.

A second kind of item bank is one that can be created from large sample datasets using
IRT modeling techniques. We have this item bank as well. Our current item banks include
the following HRQOL domains: fatigue (72 items); pain (43 items); physical functioning
(43 items); general emotional distress (48 items); cognitive complaints (35 items);
and illness-specific concerns (46 items). We have several other IRT-derived item banks
in development.

In which populations has the FACIT been used?

The FACIT Measurement System has questionnaires targeted to:

• Cancer

• HIV Disease

• Multiple Sclerosis

• Arthritis

• Parkinson's Disease

• Stroke

• Other non-life-threatening chronic illnesses or conditions

• General medical practice

How may we obtain a copy of the questionnaires, permission for use, or more information
about the FACIT Measurement System?

You may obtain user-ready copies of all available English language FACIT measures,
permission for use of a FACIT measure, and a variety of other information regarding
the FACIT Measurement System on our website at http://www.facit.orgwebcite.

How much does it cost to purchase the FACIT itself?

License for use of any English version of a FACIT measure is granted free of charge.
Collaborators are asked to agree to a simple user agreement and to register their
use of a FACIT questionnaire by completing a Collaborators' Project Information Form.
License for use of a translated questionnaire may require a fee. This decision is
made on an individual project basis according to the nature of the trial, the questionnaires
and translations to be used, the sponsor, and existing contractual arrangements.

How can we obtain scientific support during our study?

Conclusion

The Functional Assessment of Chronic Illness Therapy (FACIT) Measurement System is
a collection of health-related quality of life (HRQOL) questionnaires that assess
multidimensional health status in people with various chronic illnesses, including
cancer. The measurement system, under development since 1987, began with the creation
of a generic CORE questionnaire called the

F

unctional

A

ssessment of

C

ancer

T

herapy-

G

eneral (FACT-G). The FACT-G (now in Version 4) is a 27-item compilation of general
questions divided into four primary QOL domains: Physical Well-Being, Social/Family
Well-Being, Emotional Well-Being, and Functional Well-Being. It is appropriate for
use with patients with any form of cancer, and extensions of it have been used and
validated in other chronic illness condition (e.g., HIV/AIDS; multiple sclerosis;
Parkinson's disease; rheumatoid arthritis), and in the general population. The FACIT
Measurement System now includes over 400 questions, some of which have been translated
into more than 45 languages. Assessment of any one patient is tailored so that the
most-relevant questions are asked and administration time for any one assessment is
usually less than 15 minutes. This is accomplished both by the use of specific subscales
for relevant domains of HRQOL, or computerized adaptive testing (CAT) of selected
symptoms and functional areas. FACIT questionnaires can be administered by self-report
(paper or computer) or interview (face-to-face or telephone). Available scoring, normative
data and information on meaningful change now allow one to interpret results in the
context of a growing literature base.

Authors' contributions

Ms. Webster contributed to the conception of much of the original research, the conduct
of many of the studies, and to the writing of the manuscript. Dr. Cella contributed
to the conception of all original research, the conduct of all of the referenced studies,
and the writing of the manuscript. Dr. Yost contributed to the analysis of the data
and to the writing of the manuscript.

Acknowledgements

Over the past 15 years, more than 10,000 people have agreed to participate in research
projects that have collectively contributed to the writing of this manuscript. We
are grateful to those people for agreeing to help advance health status assessment
with no motive other than to give something back. We are also grateful to so many
of our colleagues who have contributed to the accumulated knowledge captured by the
FACIT Measurement System research program, including Elizabeth Hahn, Chih-Hung Chang,
Amy Peterman, Lauren Lent, Sonya Eremenco, Susan Yount, David Eton, Jin-Shei-Lai,
and Marianne Brady.